I’d like to add here that the pack/unpack feature should allow a studio professional to archive a project safely and predictably. Currently, it has a fatal flaw that is easy to miss.
If the .blend file uses files from different paths that share the same filename, then they get archived and appended with numerals ( .001, .007… ), but when the file is unpacked to the \textures folder, all files are written to one folder. Duplicates beyond the first-written get discarded and are gone forever. Materials all point to this one surviving file, rendering your project useless and unrecoverable.
If Blender simply wrote out those “.001…” files, that would be great. You’d still have the data and the project would work.